1. Field of the Invention
The present invention is directed to an X-radiator of the type having a protective housing with an X-ray tube accommodated therein and having a radiation protection layer containing at least one protective substance, i.e., substance which substantially impeded X-ray propagation through the protective layer.
2. Description of the Prior Art
Manufacturers of X-radiators are required to protect the personnel operating radiological systems as well as patients who are examined with radiological systems against excessive radiation exposure during the operation of the radiological system. The protective housing of X-radiators is therefore-provided with a radiation protection lining composed of a protective substance. Protective substances should effect an optimally high attenuation of the X-radiation given an optimally low layer thickness. Baryta stone, concrete, tiles and lead (in the form of metallic lead or lead alloys, lead rubber and lead glass) are standard as protective substances for radiation protection linings in radiology.
In an X-radiator disclosed in German OS 44 29 910, this radiation protection lining is formed by a lead layer arranged in the inside of the protective housing, i.e. a lead lining firmly joined to the inside of the protective housing.
U.S. Pat. No. 2,049,275 discloses that a lead layer be firmly joined to the outside of the protective housing of an X-radiator.
A multi-layer structure of radiation protection layers is known from U.S. Pat. No. 4,795,654.
The application of such lead layers is time-consuming since the lead layer must first be applied to the protective housing and then be soldered or, respectively, welded thereto or connected in some other suitable way.
When, as in the case of German OS 44 29 910, the lead layer is arranged in the inside of the protective housing, there is also the problem that the lead chemically reacts in an undesirable way with the insulating oil that is generally present in the inside of the protective housing. The lead layer must therefore be provided with a protective coat in order to suppress or at least retard the chemical reaction with the insulating oil. Complicated degreasing and coating steps are required in order to assure an adequate adhesion and durability of the protective coating.
Restoration of the protective coat of the lead layer as well as restoration of the outside of the protective housing given recycling of a protective housing returned from a customer is especially problematical given a lead layer arranged in the inside of the protective housing, as in the case of German OS 44 29 910, since the housing and the lead layer must be absolutely de-oiled and degreased for the renewal of the coats.
Although the problem of the reaction of the lead with the insulating oil does not exist given a lead layer applied to the outside of the protective housing, as in the case of U.S. Pat. No. 2,049,275, the risk of mechanical damage to the lead layer, with the consequence or impermissible emergence of radiation, does pose a problem.
Given recycling of protective housings having a lead layer arranged outside the protective housing, as in the case of U.S. Pat. No. 2,049,275, particular care must be exercised to detect damage to the lead layer and to permanently repair it.